Carton opening knife



1952 E. N. BURNETT CARTON OPENING KNIFE Filed March 7, 1950 JNVENTOR. EDWARD IV. BURNETT BY nd? ATTORNEYS Patented Jan. 15, 1952 ATENT OFFICE Edward N. Burnett, San Lorenzo, Calif., assignor to Gerber Products Company, Fremont, Mich., a corporation of Michigan Application March 7, 1950 Serial No. 148,093

4 Claims.

' 1 This invention relates to a new and useful improvements in carton opening knife, and more particularly to a knife having a dual purpose, namely to separate two cartons temporarily joined together by a fibre extension, and to slit the side wall of a carton preparatory to removing the top thereof.

It will be understood that the instant invention comprises an inexpensive, compact, and safe utensil which may be used by retail merchants, warehousemen, or the like to cut the material of ordinary fibre boxes such as corrugated containers used to pack canned and bottled merchandise. The knife blade is moveable to two positions foruse to accomplish either of. the purposes heretofore named and the knife has a further safety position wherein all sharp edges are protected so that the knife maybe handled or carried in the pocket or about the person of the user with safety. a

Further objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings in which similar characters of reference represent corresponding parts in each of the several views.

In the drawings: 7 a

Fig. 1 is a perspective of the knife as viewed in one direction with the blade in. position for severing one carton from another.

Fig. 2 is a perspective similar to Fig. l. but viewed from a different position.

Fig. 3 is a top plan of the knife with the blade in position for removing the top of a carton.

Fig. 4 is a side elevation of the structure shown in Fig. 3.

Fig. 5 is an end elevation of the structure shown in Fig. 3. r

Fig. 6 is a schematic perspective showin'g' the knife used to sever two cartons. f

Fig. 7 is a perspective showing the'knife used to remove the top of a carton. V f

Fig. 8 is a side elevation of the guard in retracted position. 1' 'j I As has been stated, the instant invention constitutes a dual purpose knife. One of its purposes is to sever two box units joined together by a fibre extension of one box glued to the adjacent box. Such boxes are illustrated and described in the co-pending application of Edward N. Burnett, Serial No. 141,150, filed January 28,1950, and further illustrated in Fig. 6 hereof. .It will be understood that referenc'e'numerals'A and B indicate two complete box units joined together by means of integral tongues II and I2 projecting outwardly from units A and B respectively and glued to upper surfaces of the adjacent box units. It will be understood that there are corresponding tongues projecting from the bottom surfaces ,of the units. -It will be further understood that in lieu of the integral tongues joining the adjacent units together, non-integral pads of cardboard or corrugated material may be glued to the surface of two units to join them together. One use of the knife which constitutes the instant invention is to sever the connecting cardboard or the top of a box or box unit by cutting into the adjoining sides without damaging the contents packed therein. These and other functions of the knife will become apparent on consideration of the description of the structure thereof which follows:

The handle l6 of the knife is preferably formed in the shape of a U-shaped channel, the opposed surfaces of the respective legs 11 and H! of the channel being spaced apart a distance only slightly greater than the thickness of the knife blade l9. Said blade [9 is provided with a hole adjacent one end thereof through which fits .a. screw 2|, said screw also passing through parallel elongated slots 22 longitudinally disposed centrally with respect to each of the legs 11 and I8. Nut 23 threaded on screw 21 when .tight'ened holds blade l9 in position longitudinally'of the handle 16. Said screw 2| constitutes a'pivot for the blade l9 so that the blade maybe manually moved from the first position illustrated in Fig. 1 to the second position illustrated in Fig. 3, it being understood that the first position is intended for use in severing one ,carton from another (see Fig. 6) and the second position is used to remove the top from a carton ,(seeFig. 7). I

J ,The blade H! in the portion opposite the end .through which screw 2! passes is provided with two cutting areas in-the vicinity of which the ,blade is sharpened, one area being useful when 'the knife is in first position and the other being useful when in second position. The first position area comprises a notch 26 cut into the top longitudinal edge of the blade so that the anterior portion of the blade resembles a hook 21 adapted to fit under tongue I I or 12 and between the adjacent sides of box units A and B when said units are being severed. Notch 2B is shaped it. by reference 11111118133135 and the edge of the and bottom edge 29. It will be seen with refer ence to Fig. 6 that after the book .21 has been inserted between unitsA and B and under tongue him the edges 28 and 29 of the "notch 2e sever I I or I2, as the operator drawsthe knife toward the cardboard or corrugated paper which constitute tongues II and I2 for iseparation of the units A and B from each other. The point of hook 21 assists in locating the knife proper position between the adjacent sides of the box units A and B so that only tongues I and t2 are cut and the other portions of box suits are not damaged.

The biade'l'e maybe swung from the position shown in Fig. 1 to the position shown in: Figs. 8 and 4 about pivot. 2|.

In such position; the tipof blade IQGXtEl'ldS beyond the endor'handle The tip of blade I9 is cut backas indicated blade is sharpened-in this zone.

Guide 37 is attachedto the handle I eby'ineans of a plurality of studs 33 fixed to-channel by l8 and projecting through slot'3'9-in' saidgtiide 31. 'The heads of said studs are peened-ov'er sothat the guide 3'! maybe moved longitudinally with respect'tohandle- I6. Guide 31- is formed with two parallel armsfl and 42 respectivelyjoined by perpendicular-connecting' oiT-setportion 43. Slot 39 is formed in arm 4' I which is adjacent and parallel to channel leg I8 and slidabiy held by studs'38. "Guide 31 is moveable to three positions, determined by'the length-of slot-39. 'In extended position off-set portion covers the poi-nt'of blade [-9 so as to prevent the sharpened edge 36 thereof from being exposed. Thus the guide 37 constitutes a safety device preventing the'user from being: injured while the knife is handled or carried on the person. This position is illustrated in dot and dash lines in Fig. 3-. A dimple ln is struck up from the surface --ofleg I8 adjacent the end thereof, saiddimple bearingagainst the undersurface'of arm 4'! and frictionally'retarding'movements of guide positive manual movement is portion 35 extends beyond the off-set portion 43 and hence the cutting portion 36 is exposed for use. The amount'said blade I9 extends may be ad usted by loosening nut 23 and sliding screw 2 I in slot'2e thereof, thus moving blade-.19 with respect to the handle I='6. As blade f9 is'moved toward the right as viewed in Fig.1, the amount the blade will project beyond the-portion 43' is decreased, whereas, as blade I9 is moved toward the left as viewed in Fig. 1, the amount which "the tip ofblade i=9 projects is increased. .Th'i's adjustment of the blade adapts: the knife for use in cutting cartons of difierent thicknesses, it

being intended that the amount which the blade projects will be adjusted so as, to coincide" with the thickness of the material being cut. with.

the blade extended the proper distance, the underside of arm 42 is placed in contact with the top of the box and the ofi-set portion 43 is placed in contact with the side being severed. The knife is then drawn along the side of the box and the cutting edge 36 of the blade I9 cuts through the side of the box. J

A third-position of adjustment results when guide '31 is fully retracted as shown in Fig. 8. The blade edge 36 is fully exposed and the guide is in operation in this position. The blade may thus 'be' used to slit the container at any position. Thus it will be seen that in the first position of adjustment of blade I9 hook 21 may be insertedbetween' two box units so that cutting edges '28and"29will sever the member joining the twomitstogether (see Fig. 6). With blade I9 in the second position of adjustment and the guide 3! in the position showing in Fig. 4, cutting edge 36 of blade I9 may be used to sever the side of the'box in order to remove the top. (see Fig. 7;) when the -guide 31 is fully retracted, as in FigLB; the-sharp edgebfbiado 19 may be used-to out into aearton or for general cutting purpose. When the guide 31 is projected it acts as asaiety guard-to prevent-the blade I9 from claims.

' I claim:

'1. A knife comprising a channel-shapedhandl'e anda blade' having" a"re1atively thin anterior portion having alongi'tudmal edge, a notch cut into said longitudinaledg'e', said notch having a bottom edge substantially paralle'lito said longitudinal .edge' andlspaced inwardly with respect thereto a first connecting edge slanted inwardly and forwardly from said longitudinal edge to said bottom edge-and a second connecting edge, and a'sharpened slitting edge on said blade located at the anterior end of said blade disposed at. an acute angle .with respect to said longitudinal edge, saidlblade being pivotally'connected to said handle and arra'nged to be located in two positions, in one-of said-posi'tionssaid notch portion of said blade extending :beyond one end of said handle and in the othenof. said positions said notch portion being concealed within the channel of said handle and said. slitting edge projecting beyond the opposite end of said handle.- 7

2.- A knife comprising achan-nel-shaped handle,

a guide member attached to said handle, and

at the anterior end ofsa-id blade disposed at an acute angle with respect to said longitudinal edge, said blade. being pivotally connected to said handle -a' nd-. arranged--tobe located intwo positions', in .one oilsaid; positions said notch portion of said. blade-extending .beyond one end of said handle. and. inthe other of said. positions said notch portion .bil'lfiddilddld Within the channel or said handle and said slitting edge projecting beyond the opposite end of said handle, said.

guide comprising a first arm, a second arm parallel thereto and a portion connecting said arms and disposed substantially normal thereto, said arms being substantially parallel to said blade, said first arm being connected to said handle, the under-surface of said second arm and a surface of said connecting portion constituting locating surfaces controlling the penetration and location of said blade with respect to a workpiece.

3. A knife comprising a channel shaped handle, a guide member attached to said handle, and a blade having a relatively thin anterior portion having a longitudinal edge, a notch cut into said longitudinal edge, said notch having a bottom edge substantially parallel to said longitudinal edge and spaced inwardly with respect thereto a first connecting edge slanted inwardly and forwardly from said longitudinal edge to said bottom edge and a, second connecting edge, and a sharpened slitting edge on said blade located at the anterior end of said blade disposed at an acute angle with respect to said longitudinal edge, said blade being pivotally connected to said handle and arranged to be located in two positions, in one of said positions said notch portion of said blade extending beyond one end of said handle and in the other of said positions said notch portion being concealed within the channel of said handle and said slitting edge projecting beyond the opposite endof said handle, said guide comprising a first arm, a second arm parallel thereto and a portion connecting said arms being substantially normal to said blade, said first arm being slidably connected to said handle, the under-surface of said second arm and a surface of said connecting portion constituting locating surfaces controlling the penetration and location of said blade with respect to a workpiece, said guide being moveable relative to said blade in an extended and retracted position, said slitting edges being shielded when said guide is in extended position.

4. A knife comprising a channel-shaped handle and a blade, said blade having a relatively thin anterior portion with a sharpened anterior, longitudinally disposed first edge and a hooked extremity portion projecting transversely outwardly from said first edge, the outwardly extending edge of said hooked extremity adjacent said first edge being sharpened, said blade also having a sharpened slitting edge located at the anterior end of said blade disposed at an acute angle with respect to said first edge, said blade being pivotally connected to said handle partially disposed within said channel and arranged to be located in two positions, in one of said positions, said hooked extremity of said blade extending beyond one end of said handle and in the other of said positions said notch portion being concealed within the channel of said handle and said slitting edge projecting beyond the opposite end of said handle.

EDWARD N. BURNETT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,121,469 Budlong Dec. 15, 1914 1,527,220 Pyle Feb. 24, 1925 1,562,429 Unsinger Nov. 17, 1925 1,796,870 Huhn Mar. 17, 1931 2,348,429 Walker May 9, 1944 

